西安地裂缝场地动力响应规律及影响因素分析
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摘要
在地裂缝密集分布的西安地区,建筑"傍缝而建"的现象非常普遍,地裂缝的存在严重制约了城市建设用地的有效利用和规划。为研究地裂缝对场地动力响应的影响,分析地震动作用下地裂缝场地动力响应规律及其影响范围,以西安地裂缝为研究对象,基于室内振动台试验及FLAC~(3D)数值模拟,分析地裂缝场地动力响应中的加速度幅值动力响应特征。在此基础上,进一步分析不同地震波类型、地裂缝破裂面倾角、地震动强度、地裂缝两侧土层错距对地裂缝场地动力响应的影响。研究表明:地裂缝对场地动力响应影响明显,表现为地裂缝一定范围内峰值加速度呈"带状"分布,即地裂缝处峰值加速度最大,随着距地裂缝越来越远,峰值加速度逐渐减小后趋于稳定,带状分布范围上盘约30 m,下盘约20 m;地裂缝场地动力响应表现出明显的"上盘效应",即上盘峰值加速度略大于下盘;地震动强度对地裂缝场地动力响应影响明显,地裂缝倾角、地裂缝两侧土层错距、地震波对地裂缝场地动力响应均无明显影响
Ground fissures are densely distributed in the Xi'an area. Buildings that are "near the seam and built" are very common, which influences land use and planning in the urban zones. To research the dynamic effects of the ground fissures, this paper chose the Xi'an ground fissure site as the object of the research. After performing the shaking table test and FLAC~(3 D) numerical simulation, the dynamic response characteristics, such as acceleration amplitude of the ground fissure site, were analyzed. On this basis, the influence of different types of seismic waves, the fracture surface's dip angle at the ground fissure, the intensity of ground motion, and the soil dislocation on both sides of the ground fissures were further analyzed. The results showed that the ground fissures had an obvious effect on the dynamic response of the site, and that the peak acceleration, in a certain range, was zonal in distribution, i.e., the peak acceleration at the ground fissure was the largest. With increasing distance from the ground fissure, the peak acceleration gradually declined, becoming stable; the range of the zonal distribution was about 30 m in the hanging wall, and about 20 m in the footwall. The dynamic response of the ground fissure site showed an obvious "hanging wall effect," i.e., the peak acceleration of the hanging wall was slightly larger than that of the footwall. The ground motion intensity had an obvious effect on the dynamic response of the ground fissure site, while the dip angle of the ground fissure, seismic waves, and the soil dislocation on both sides of the ground fissures had no obvious effect on the dynamic response of the ground fissure site.
Ground fissures are densely distributed in the Xi'an area. Buildings that are "near the seam and built" are very common, which influences land use and planning in the urban zones. To research the dynamic effects of the ground fissures, this paper chose the Xi'an ground fissure site as the object of the research. After performing the shaking table test and FLAC~(3 D) numerical simulation, the dynamic response characteristics, such as acceleration amplitude of the ground fissure site, were analyzed. On this basis, the influence of different types of seismic waves, the fracture surface's dip angle at the ground fissure, the intensity of ground motion, and the soil dislocation on both sides of the ground fissures were further analyzed. The results showed that the ground fissures had an obvious effect on the dynamic response of the site, and that the peak acceleration, in a certain range, was zonal in distribution, i.e., the peak acceleration at the ground fissure was the largest. With increasing distance from the ground fissure, the peak acceleration gradually declined, becoming stable; the range of the zonal distribution was about 30 m in the hanging wall, and about 20 m in the footwall. The dynamic response of the ground fissure site showed an obvious "hanging wall effect," i.e., the peak acceleration of the hanging wall was slightly larger than that of the footwall. The ground motion intensity had an obvious effect on the dynamic response of the ground fissure site, while the dip angle of the ground fissure, seismic waves, and the soil dislocation on both sides of the ground fissures had no obvious effect on the dynamic response of the ground fissure site.
引文
[1] 崔臻,盛谦,冷先伦,等.近断层地震动对大型地下洞室群地震响应的影响研究[J].岩土力学,2013,34(11):3213-3220,3228.CUI Zhen,SHENG Qian,LENG Xianlun,et al.Effects of Near-fault Ground Motion on Seismic Response of Underground Cacerns[J].Rock and Soil Mechanics,2013,34(11):3213-3220,3228.
[2] 黄博,李玲,梁甜,等.考虑Gmax附加衰减的场地地震响应离心机试验数值模拟[J].岩土力学,2014,35(7):2057-2063.HUANG Bo,LI Ling,LIANG Tian,et al.Numerical Simulation for Site Seismic Response of Centrifuge Model Test Considering Effect of Additional Attenuation of Gmax[J].Rock and Soil Mechanics,2014,35(7):2057-2063.
[3] 汪明武,赵奎元,朱其坤,等.可液化场地微型桩地震响应特性研究[J].岩土力学,2016,37(6):1543-1549.WANG Mingwu,ZHAO Kuiyuan,ZHU Qikun,et al.Seismic Responses of a Micropile in Liquefiable Soils[J].Rock and Soil Mechanics,2016,37(6):1543-1549.
[4] 高峰,孙常新,谭绪凯,等.不同埋深隧道的地震响应振动台试验研究[J].岩土力学,2015,36(9):2517-2522,2531.GAO Feng,SUN Changxin,TAN Xukai,et al.Shaking Table Tests for Seismic Response of Tunnels with Different Depths[J].Rock and Soil Mechanics,2015,36(9):2517-2522,2531.
[5] 李伟华,赵成刚,杜楠馨.软弱饱和土夹层对地铁车站地震响应的影响分析[J].岩土力学,2010,31(12):3958-3963,3970.LI Weihua,ZHAO Chenggang,DU Nanxin.Analysis of Effects of Saturated Soft Interlayer on Seismic Responses of Metro Station[J].Rock and Soil Mechanics,2010,31(12):3958-3963,3970.
[6] GB50011-2010:建设抗震设计规范[S].北京:中国建筑工业出版社,2010.GB50011-2010:Code for Seismic Design of Building[S].Beijing:China Architecture & Building Press,2010.
[7] 石玉成,陈丙午.非发震断层的地震效应问题[J].西北地震学报,1994,16(1):12-20.SHI Yucheng,CHEN Bingwu.Effects of Non-Causative Faults on Earthquake Damages[J].Northwestern Seismological Journal,1994,16(1):12-20.
[8] 周正华,张艳梅,孙平善,等.断层对震害影响的研究[J].自然灾害学报,2003,12(4):20-24.ZHOU Zhenghua,ZHANG Yanmei,SUN Pingshan,et al.Study on Effect of Fault on Seismic Damage[J].Journal of Natural Disasters,2003,12(4):20-24.
[9] 刘向峰,王来贵.非发震断层场地地震动力响应特性研究[J].辽宁工程技术大学学报(自然科学版),2005,24(1):48-50.LIU Xiangfeng,WANG Laigui.Study on Earthquake Dynamic Response of Non-causative Faults Site[J].Journal of Liaoning Technical University (Natural Science Edition),2005,24(1):48-50.
[10] 刘向峰.采动损伤地层结构地震响应研究[D].阜新:辽宁工程技术大学,2005.LIU Xiangfeng.Study on Seismic Response of Strata Structure with Mining Damage[D].Fuxin:Liaoning Technical University,2005.
[11] 孙崇绍.西安市地裂缝地震效应的理论分析[J].西北地震学报,1983,5(2):73-80.SUN Chongshao.The Theoretical Analysis on the Seismic Effect of Ground Fissures in Xian[J].Northwestern Seismological Journal,1983,5(2):73-80.
[12] 刘聪,彭建兵,陈立伟,等.西安地裂缝场地地震效应分析[J].工程地质学报,2012,20 (6):979-985.LIU Cong,PENG Jianbing,CHEN Liwei,et al.Finite Element Analysis of Seismic Effects on Ground Fissures in Xi’an[J].Journal of Engineering Geology,2012,20 (6) :979-985.
[13] 陈立伟.地裂缝扩展机理研究[D].西安:长安大学,2007.CHEN Liwei.Study on the Propagation Mechanism of Ground Fissures[D].Xi'an:Chang'an University,2007.
[14] 李仕栋,罗奇峰.不同倾角断层对场地动力放大效应的分析[J].地震研究,2004,27(3):283-286.LI Shidong,LUO Qifeng.Analysis of Magnification Effect of Faults with Various Rake Angles to Site Dynamic Response[J].Journal of Seismological Research,2004,27(3):283-286.
[15] LOMBARDO G,RIGANO R.Amplification of Ground Motion in Fault and Fracture Zones:Observations from the Tremestieri Fault,Mt.Etna (Italy)[J].Journal of Volcanology and Geothermal Research,2006,153(3-4):167-176.
[16] MAVROEIDIS G P,PAPAGEORGIOU A S.A Mathematical Representation of Near-fault Ground Motions[J].Bulletin of the Seismological Society of America,2003,93(3):1099-1131.
[17] LOH C H,WU T C,HUANG N E.Application of the Empirical Mode Decomposition-Hilbert Spectrum Method to Identify Near-fault Ground-motion Characteristics and Structural Responses[J].Bulletin of the Seismological Society of America,2004,91(5):1339-1357.
[18] SMITH W D.A Nonreflecting Plane Boundary for Wave Propagation Problems[J].Journal of Computational Physics,1974,15(4):492-503.
[19] PITARKA A,IRIKURA K,IWATA T,et al.Three-Dimensional Simulation of the Near-fault Ground Motion for the 1995 Hyogo-Ken Nanbu (Kobe),Japan,Earthquake[J].Bulletin of the Seismological Society of America",1998,88 (2):428 -440 .
[20] PITARKA A,SOMERVILLE P,FUKUSHIMA Y.Simulation of Near-fault Strong-ground Motion Using Hybrid Green's Functions[J].Bulletin of the Seismological Society of America,2000,90(3):566-586.
[21] RICHARDS P G.Dynamic Motions near an Earthquake Fault:A Three-Dimensional Solution[J].Bulletin of the Seismological Society of America,1976,66(1):1-32.
[22] 陈育民,徐鼎平.FLAC/FLAC3D基础与工程实例[M].北京:中国水利水电出版社,2009.CHEN Yuming,XU Dingping.FLAC/FLAC3D Foundation and Engineering Example[M].Beijing:China Water Power Press,2009.
[23] 雷小芹,杨果林.边界面模型在FLAC3D中的开发及验证[J].岩土力学,2012,33(2):635-640.LEI Xiaoqin,YANG Guolin.Development and Verification of Bounding Surface Model in FLAC3D[J].Rock and Soil Mechanics,2012,33(2):635-640.
[24] 慕焕东.地裂缝场地地震放大效应研究[D].西安:长安大学,2014.MU Huandong.Study on the Seismic Amplification Effect on Site with Ground Fissure[D].Xi'an:Chang'an University,2014.
[25] 慕焕东,邓亚虹,彭建兵.西安地区地裂缝带黄土动力特性试验研究[J].工程地质学报,2014,22(5):951-957.MU Huandong,DENG Yahong,PENG Jianbing.Experimental Research on Loess Dynamic Characteristics at Ground Fissure Belt in Xi'an Area[J].Journal of Engineering Geology,2014,22(5):951-957.
[2] 黄博,李玲,梁甜,等.考虑Gmax附加衰减的场地地震响应离心机试验数值模拟[J].岩土力学,2014,35(7):2057-2063.HUANG Bo,LI Ling,LIANG Tian,et al.Numerical Simulation for Site Seismic Response of Centrifuge Model Test Considering Effect of Additional Attenuation of Gmax[J].Rock and Soil Mechanics,2014,35(7):2057-2063.
[3] 汪明武,赵奎元,朱其坤,等.可液化场地微型桩地震响应特性研究[J].岩土力学,2016,37(6):1543-1549.WANG Mingwu,ZHAO Kuiyuan,ZHU Qikun,et al.Seismic Responses of a Micropile in Liquefiable Soils[J].Rock and Soil Mechanics,2016,37(6):1543-1549.
[4] 高峰,孙常新,谭绪凯,等.不同埋深隧道的地震响应振动台试验研究[J].岩土力学,2015,36(9):2517-2522,2531.GAO Feng,SUN Changxin,TAN Xukai,et al.Shaking Table Tests for Seismic Response of Tunnels with Different Depths[J].Rock and Soil Mechanics,2015,36(9):2517-2522,2531.
[5] 李伟华,赵成刚,杜楠馨.软弱饱和土夹层对地铁车站地震响应的影响分析[J].岩土力学,2010,31(12):3958-3963,3970.LI Weihua,ZHAO Chenggang,DU Nanxin.Analysis of Effects of Saturated Soft Interlayer on Seismic Responses of Metro Station[J].Rock and Soil Mechanics,2010,31(12):3958-3963,3970.
[6] GB50011-2010:建设抗震设计规范[S].北京:中国建筑工业出版社,2010.GB50011-2010:Code for Seismic Design of Building[S].Beijing:China Architecture & Building Press,2010.
[7] 石玉成,陈丙午.非发震断层的地震效应问题[J].西北地震学报,1994,16(1):12-20.SHI Yucheng,CHEN Bingwu.Effects of Non-Causative Faults on Earthquake Damages[J].Northwestern Seismological Journal,1994,16(1):12-20.
[8] 周正华,张艳梅,孙平善,等.断层对震害影响的研究[J].自然灾害学报,2003,12(4):20-24.ZHOU Zhenghua,ZHANG Yanmei,SUN Pingshan,et al.Study on Effect of Fault on Seismic Damage[J].Journal of Natural Disasters,2003,12(4):20-24.
[9] 刘向峰,王来贵.非发震断层场地地震动力响应特性研究[J].辽宁工程技术大学学报(自然科学版),2005,24(1):48-50.LIU Xiangfeng,WANG Laigui.Study on Earthquake Dynamic Response of Non-causative Faults Site[J].Journal of Liaoning Technical University (Natural Science Edition),2005,24(1):48-50.
[10] 刘向峰.采动损伤地层结构地震响应研究[D].阜新:辽宁工程技术大学,2005.LIU Xiangfeng.Study on Seismic Response of Strata Structure with Mining Damage[D].Fuxin:Liaoning Technical University,2005.
[11] 孙崇绍.西安市地裂缝地震效应的理论分析[J].西北地震学报,1983,5(2):73-80.SUN Chongshao.The Theoretical Analysis on the Seismic Effect of Ground Fissures in Xian[J].Northwestern Seismological Journal,1983,5(2):73-80.
[12] 刘聪,彭建兵,陈立伟,等.西安地裂缝场地地震效应分析[J].工程地质学报,2012,20 (6):979-985.LIU Cong,PENG Jianbing,CHEN Liwei,et al.Finite Element Analysis of Seismic Effects on Ground Fissures in Xi’an[J].Journal of Engineering Geology,2012,20 (6) :979-985.
[13] 陈立伟.地裂缝扩展机理研究[D].西安:长安大学,2007.CHEN Liwei.Study on the Propagation Mechanism of Ground Fissures[D].Xi'an:Chang'an University,2007.
[14] 李仕栋,罗奇峰.不同倾角断层对场地动力放大效应的分析[J].地震研究,2004,27(3):283-286.LI Shidong,LUO Qifeng.Analysis of Magnification Effect of Faults with Various Rake Angles to Site Dynamic Response[J].Journal of Seismological Research,2004,27(3):283-286.
[15] LOMBARDO G,RIGANO R.Amplification of Ground Motion in Fault and Fracture Zones:Observations from the Tremestieri Fault,Mt.Etna (Italy)[J].Journal of Volcanology and Geothermal Research,2006,153(3-4):167-176.
[16] MAVROEIDIS G P,PAPAGEORGIOU A S.A Mathematical Representation of Near-fault Ground Motions[J].Bulletin of the Seismological Society of America,2003,93(3):1099-1131.
[17] LOH C H,WU T C,HUANG N E.Application of the Empirical Mode Decomposition-Hilbert Spectrum Method to Identify Near-fault Ground-motion Characteristics and Structural Responses[J].Bulletin of the Seismological Society of America,2004,91(5):1339-1357.
[18] SMITH W D.A Nonreflecting Plane Boundary for Wave Propagation Problems[J].Journal of Computational Physics,1974,15(4):492-503.
[19] PITARKA A,IRIKURA K,IWATA T,et al.Three-Dimensional Simulation of the Near-fault Ground Motion for the 1995 Hyogo-Ken Nanbu (Kobe),Japan,Earthquake[J].Bulletin of the Seismological Society of America",1998,88 (2):428 -440 .
[20] PITARKA A,SOMERVILLE P,FUKUSHIMA Y.Simulation of Near-fault Strong-ground Motion Using Hybrid Green's Functions[J].Bulletin of the Seismological Society of America,2000,90(3):566-586.
[21] RICHARDS P G.Dynamic Motions near an Earthquake Fault:A Three-Dimensional Solution[J].Bulletin of the Seismological Society of America,1976,66(1):1-32.
[22] 陈育民,徐鼎平.FLAC/FLAC3D基础与工程实例[M].北京:中国水利水电出版社,2009.CHEN Yuming,XU Dingping.FLAC/FLAC3D Foundation and Engineering Example[M].Beijing:China Water Power Press,2009.
[23] 雷小芹,杨果林.边界面模型在FLAC3D中的开发及验证[J].岩土力学,2012,33(2):635-640.LEI Xiaoqin,YANG Guolin.Development and Verification of Bounding Surface Model in FLAC3D[J].Rock and Soil Mechanics,2012,33(2):635-640.
[24] 慕焕东.地裂缝场地地震放大效应研究[D].西安:长安大学,2014.MU Huandong.Study on the Seismic Amplification Effect on Site with Ground Fissure[D].Xi'an:Chang'an University,2014.
[25] 慕焕东,邓亚虹,彭建兵.西安地区地裂缝带黄土动力特性试验研究[J].工程地质学报,2014,22(5):951-957.MU Huandong,DENG Yahong,PENG Jianbing.Experimental Research on Loess Dynamic Characteristics at Ground Fissure Belt in Xi'an Area[J].Journal of Engineering Geology,2014,22(5):951-957.